Is there a good 3rd party application or plug-in to generate decent looking reports with the options and features we need like putting summaries on bottom of the groups, changing colors, fonts, etc., ?
Tableau server is good tool and now you can pull reports inside salesforce using canvas feature.
Qlikview is another tool that can generate good looking reports
If you use a third party ODBC driver (Progress have a nice one), you can use pretty much any reporting software out there. I recommend you to try several of them, and you can start with DBxtra which does what you want and much more, also, it's easy to use as you can create a report by pure drag and drop.